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( e i J. E. GLEASON. "es ee MACHINE PoR PORMIN@ GEAR TBETH.

Inventar: a 5 ww, @Mm

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9 Sheets-Sheet 2.

0mm J. E. GLBASON.

MACHINE FOR' PORMING GEAR TBBTH.

No. 605,249. Y Patented June 7,1898.

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me Noms PETERS co. PHoYaMmo., wuumamw, ur.

(No Model.) J E GLEASON 4 9 sheetssheen 3.

MACHINE FOR FORMING GEAR TBBTH.

Patentd June 7,

n llwy.

' 9 Sheets-Sheet 4.

J. E. GLEASON. MACHINE PoR FORMING GEAR TBBTH.

(No Model.)

No. 605,249. Patented Jung?, 1898.`

(No Model.) J' E. GLEASONI 9 Sheets- Sheet 5.

MACHINE FOR FDRMING GEAR TBETH.

No. 605,249 Patented June'?, 1898.

v4 f# r* C3 Y Z# '11,11'

(No Model.) 9 Sheets-Sheen 6.

J.E.GLEAS0N.' MACHINE FOR FORMING GEAR TEETH.

No. 605,249. Patented June '7, 1898.

(No Model.) v 9 Sheets-Sheet 7. J. E; GLEASON.

MACHINE FOR FORMING GEAR TEETH.

Patented June 7,1898.

(No Model.) I' 9 Sheets-Sheet 8.

' J. E. GLEASON.`

MACHINE FOR PORMING GEAR TEETH.

No. 605,249. Patented June 7,1898.

Inventor.' fmgdvw,

r9 sheets-sheen 9;

( No Model.)

J E GLEASON MAGHINB PoR FORMING GEAR TBBTH,

No. 605,249. Patented June 7,1898.

NITE@ STATES Erica.

JAMEs E. eLEAsoN, oERoonEsTER, NEW vomi, AssieNoR Vro THE eLEAsoN Toor. coMPANY,"'oE SAME PLACE.

MACHINE FOR FORMING ,cEAR-TEETH..

srEcIFIcATIoN forming part of Letters Patent ivo. 605,249, dated Jun@ v, 1898.

` imputation nea raam 23,1897. serial No. 624,557. (Nonnen 1 To all t whom t `mayr 4con/cervi,.-

Bea known um 1, JAMES E. emisor, of

Rochester, in the county of Monroe and State p of New York, have invented a new and useful Improvement in Machines for Forming Gear- Teeth, which improvement is fully set forth inthe following specication and shown in the accompanying drawings.

My invention relates to machines for forming the teeth of gears in which rotary toothed cutters are employed; and the invention is designed more particularly for forming the teeth of bevelgears of comparatively small diameters, butadapted also to form the teeth of spur-gears.

In my improved gear-tooth cutter a conecenter isestablishedand means are provided to set the blank-gear with reference to it and also to give the cutter various motions,includ ing a swinging motion, relating to the conecenter. Means are 'also provided for rocking the gear while being acted upon by the cutter and for giving the latter lateral intermittent motion during the operation of forming the teeth of a gear.l Micrometric .adjustments are provided for the cutter and for the rocking of the blank-gear, the machine being designed to form and complete Athe teeth of a gear at one operation-that is to say, while the blank is turned once around upon its axis or through one complete revolution.

The invention is hereinafter fully described, and more particularly pointed out in the claims.

Referring to the drawings, Figure 1 is a front elevation of my improved machine for forming gearteeth, some minor parts being omitted. Fig. 2 is a transverse section through the spindle and some associated parts on the line 2 2 in Fig. 1. Fig. 3 is a side elevation of the machine, seen as indicated by arrow 3 in Fig 1, the door and other parts being omitted and parts broken away. Fig. 4 is a vertical section of parts at the left of the machine, taken on the dotted line 4 4 in Fig. 3 and viewed as indicated by the arrow pointed arrow in Fig. 6, parts being sectioned. Fig.

6 is an elevation of the traveling wheelwith some associated parts, a part of the crownl the toothed parts.

segment carrier being sectioned away to show Fig. ,7 shows the reverse side of one of the arresters. Fig. S is a plan of the lower parts of the machine, the main upper parts and some minor parts being omitted.` Fig. 9 is a similar plan with all of the parts above the bracket or linee omitted. Fig. 10`is a crosssectionof the column and `other partson the dotted line 10 10 inFig. 1, showing interior parts. Fig. 11 is -a vertical cross-section of the reciprocating bar or reciprocator and some associated parts on the dotted line,11 11 in Fig. 8. Fig. 12 is a side elevation of the toothed reciprocator and rocking wheel with some associated parts. Fig.

13 is an elevation of the reciprocator,rock- `in Fig. 1, some minor parts being omitted. Fig. 15 is a vertical longitudinal section of the cutter-spindle and other parts, taken on the `dotted lines 15 in Figs. 1 and 8, parts being` broken away. Fig. 16 shows the interiorof the 10am-wheel and contained parts,seen as indicated byarrowin Fig. 15. Fig. 17 is a plan of a part of the cutter-carrier and cam-wheel,show

ingthe device for micrometrically adjusting the cutter, parts being horizontally sectioned as on the dotted lines 17 in Figs. landll. Fig. 18 is a view of a part ofthe cutterfcarrier, cam-wheel, and the micrometric adjusting device, seen asindicated byarrowin Fig. 17. Fig. 19 is' a rear elevation of the machine, seen in the direction opposite to that in which Fig. 1 is seen, a part ,being broken away and some minor parts omitted. Fig. 20vis a view of the spiudle'carrierand associatedlparts, seen as indicated byarrow20 in Fig. 1, parts being sectioned on the dotted line at the point of the arrow. Fig. `21 is ajlongitudinal section of the blank-gearspindle and associated parts, taken Von the dotted line 21 in Fig. 1, condensed as to length. Fig. 22 shows aportion of the toothed-spindle barrel andthe op` erating-pinion. Fig. 23 is -anelevation of the indexing mechanism, seen asindicated by arrow 23 in Figs. 1 and 20, parts being `longi- IOO tudinally sectioned as on the dotted `line at the point of the arrow in Fig. 20. Fig. 24 is an elevation of parts of the indexing mechanism, showing the detent and other parts, parts being sectioned on a plane coinciding with the axis of the operating-crank. Fig. 25 is a longitudinal section of the parts at the righthand end of the double-pinion shaft, showing the shiftable key for the pinions. Fig. 26 is a transverse section of the parts, taken on the dotted line 26 in Fig. 25. Fig. 27 is a transverse section of the shiftable key through the bit. Fig. 2S is a side elevation of a part of the blank-gear arbor and starting-ring with parts broken away. Fig. 29 is an end view of the arbor and expander with part of a gear in place thereon. Fig. 30is an elevation of the main parts of the mechanism for rocking the spin'dle, parts being shown in various positions by full and dotted lines, parts being broken away. Fig. 31 is a rear elevation of parts, showing the back shaft and the manner of holding the same. Fig. 32 is a View of parts, seen as indicated by arrow in Fig. 31, the back shaft being transversely sectioned on the dotted line 32 in Fig. 31.

side elevation of a cutter. Fig. 34 is a plan of the cutter-carrier and other parts controlling the cutter, parts being shown in two positions by full and dotted lines. Fig. 35 is an outline plan of parts supported by the knee and other parts above the column, parts being shown in two positions by full and dotted lines. Fig. 36 shows in outline the manner in which the cutter acts upon a' gear-tooth. Fig. 37 is a plan in outline, better showing the swinging motion of the cutter. Fig. 3S shows in outline the lateral .motion ofthe cutter. Fig. 39 is an elevation of the main parts of the feed mechanism, parts being shown in two positions by full and dotted lines. Fig. 40 is an elevation of parts of the trip for the feed, parts being sectioned as on the dotted lines 40 in Figs. 14 and 39, parts being shown in two positions by full and dotted lines. Fig. 41 is a view of the under side of the baseblock, showing the V-shaped pivot-tongue.

Fig. 42 is a skeleton iigure showing the rela-l tion of various shafts. Fig. 43 is a side elevation of parts of the indexing mechanism, parts being broken away. Fig. 44 is an axial section of the double gearand some associated parts on the dotted line 44 in Fig. 3. Fig. 45

is an elevation of part of the traveling Wheel.

Figs. 1, 3, and 3 to 10, inclusive, and 12,14, 19, 31,32,35,41,and 42 are drawn to a scale of about one-sixth full size; Figs. 2, 4, 6, 13, 15, 16, and 20 to 23, inclusive, and 30, 34, 39, 43, and 44 to a scale about one-third size; Figs. 11, 17, 18,

' 24, 25, 27, and 37 Yto a scale about one-half size; Figs. 5, 7, and 26 to a scale about twothirds size, and Figs. 28, 29, 33, 3S, 40, and 45 to a scale about full size. Fig. 36 is drawn to an exaggerated scale to show more clearly the matter wished to be brought out.

Referring to the parts shown, A in the various figures is a hollow prismatic column of iron adapted to stand upright upon the i'loor B, which column acts as a frame for supportby bolts f, Figs. 3 and 19. 3 overhangs the top of the column and projects over the bracket C and the extended part F l of the column.

Fig. 33 is a 3 adapted to movealong the vertical plane face g of the segment Gr, concentric grooves g and f h being formed in the face of the segment to guide the carrierin its movements therealong.

ing the operating parts of the machine. The column is formed at its base with a horizontally-extended part F, giving breadth to the base and for other purposes.

C, Figs. 1, 9, and 14, is a horizontal knee or bracket for supporting the cutter and other parts, adapted to move in vertical directions along ways D upon a face of the column. This bracketis supplied with. a gib a, contiguous with the ways D and held by set-screwsb.

E is a vertical screw,preferably formed with a square thread four to the inch, for controlling the bracket. This screw is headed in a shelf c of the bracket, as appears in Figs. 14 and 19, with set-nuts d above the shelf to hold it in place, the nut e for the screw resting in the part F of the column.

Gr is a curved segment ofA iron secured to the upper horizontal end or top of the column This segment H, Figs. 1, 14, and 20, is a spindle-carrier The grooves or races g and 7L are concentric with thecone-center of the machine, and the carrier H constitutes a holder for the various parts controlling the blank gear and the blank-gear itself.

I, Figs. 1, 2, 3, 20, and 21, is a spindle for carrying the blank-gear K to be cut, the spindle being held in a spindle-barrel L, su pported in the spindle-carrier ll.

N, Figs. 1, 8, 14, 15, 13, and 34, isa-cuttercarrier 'adapted to move longitudinally in a carriage O, the latter being adapted to slide horizontally upon ways i of a base-block P, resting directly upon the bracket C.

The cutter, Fig. 33, which is circular and toothed, is driven by means of a belt running upon a step-pulley R, Figs. 1, 3, and 10, held upon a horizontal shaft S, extending through the lower part of the column and resting in bearings T T, secured to the column.

U, Figs. 1, 9, 10, 14, and 19, is a vertical shaft connected with the shaft S by mitergears 7s Z, held in bearings m n in the bracket C and the part F of the column, respectively. This shaft is adapted to slide longitudinally through the gear Z, the latter being provided with an ordinary feather occupying a groove or spline o in the shaft, so that the shaft and gear must turn together. The shaft is pro vided at its upper end with a miter-gear p, adapted to drive a horizontal shaft r, Fig. 42, by engaging a miter-gear s on said shaft r. The gear p is bedded in the upper surface of IOO IZO

the bracket C, the points of the teeth slightly projecting thereabove. The shaft r extends obliquely across a bearing in the base-block P and is provided at its opposite end with ay the base-block, havinga bevel-gear @,engaged by the-gear t on the shaft u. The axes of the shafts r and u are in the same horizontal a tapered arbor a', fitted in the end of the spindle, the cutter being pressed between collars b b' on the arbor by means of a nut c', threaded thereon. A key d', rigid with the arbor and occupying a corresponding cavity in the spindle WV, causes the cutter to always turn with the spindle. From this description of parts and their relation with each other the manner in which the cutter is rotated by means of a belt upon the pulley R will be understood. y

In forming the teeth of gears of different sizes and diameters it becomes necessary to change the elevation of the bracket C and incumbent parts, including the cutter.

e', Figs. 1, 14:, and 19, is a short horizontal shaft supported in a hanger f secured to the bracket, provided at its inner end with a bevelpinion g in position to engage a bevel-gear h', rigid with the elevating-screw E. At its outer end the shaft is reduced and formed to receive a wrench or crank for turning it.

z" is a graduated ,disk rigid with or a part of thehanger f', and the shaft is formedwith a shiftable index 7c', having its point traversing the graduated surface of the disk when the shaft is turned, by means of which thev elevation of the cutter may be finally adjusted. The disk is divided into one hundred and twenty-five equal parts. Then if the shaft be turned to carry the index over one space, for example, the cutter will be elevated or depressed to the extent of one one-hundredand-twenty-iifth parts of one-eighth of an inch, or one one-thousandth of an inch, the gear h and pinion g being two to one and the screw four to the inch lead. The index is clamped onto the shaft, so as to hold with moderate friction, but so as to be shifted at any timeto point to any particular divisionmark on the disk.

The cutter is fed against the blank-gear by feeding mechanism which moves the carriage O along the slides or ways of the base-block P. This is effected by'means of the ordinary feed-screw Z, Fig. S, between the ways, the

nut for the screw (not shown) being of ordinary construction and secured to the under surface of the carriage O.

m, Figs. l, 8, 14, and 39, is a worin-gear rigid with the overhanging end of the feedscrew, in position to be actuated by a worm fn, turned from the back shaft u. A feedshaft o' rests in a holder p at the end of the base-block P, beneath the feed-screw, to the above described.

overhanging endj of which shaft is'secured a friction-.disk r. The axis of the feed-shaft is horizontal and in the plane of the axis of the back shaft u, the two axes forming a right angle. An extended reduced part of the back shaft in front of the disk r (see also Fig. 19) holds a friction-ring s', of rawhide or other yielding material, in position to bear against the face of the friction-disk, as shown.Y Now when the back shaft is rotatedV it will cause the feed-screw Z to turn and so move the oarriage O, with the cutter, along the base-block P. The friction-ring s is carried by a suitable holder t', splined on the back shaft and turning therewith. By means of shifting the friction-ring toward or from the center ofthe disk r'. the feed may be regulated at pleasure.

A tripping device is arranged to stop or throw oft the feed after the cutter has passed across the blank-gear. A trip-stud u, Figs. 1, 8, and 14, is provided to occupyahorizontal dovetail groove o inthe side of the carriage O.

w' is a horizontal trip-rod held in bearings fr projecting from the side of the baseblock P. Upon the trip-rod is placed a movable dog y', adapted to be encountered by the stud u as the carriage advances. The holder p is formed with a downwardly-projecting arm` d2, Figs. 1, 14E, 19, and 39, pivoted upon a second arm e2, rigid with the base-block P, so as to swing in a vertical plane toward or from thefeed-screw, as indicated in Fig. 39. The holder is also provided with a rigid arm a', Figs. 1, 8, 14., and 39 adapted to receive l within an opening a2 the enlarged end or head b2 of the trip-rod, asfully shown in Fig. 40.

Directly back of the head b2 is a notch c2, adapted to receive the arm a' when the rod is the machine is feeding the head b2 of the rod occupies the opening in the arm and holds the worm n up against the gear m and also the `friction-disk fr snugly against the frictionring 3'; but when from the feed motion the stud u in the carriage O encounters the dog y on the trip-rod the latter will be moved to the dotted position shown in Figi-10, allowing the arm e' to drop into the notch c2, as

The holder p, with its incumbent parts, drops from gravity when the notch c2 is presented to the trip-arm, which throws the Worma away from its gear fm. and the disk fr out of contact with the frictionring s'. (Clearly shown in Fig. 39.) This at i moved longitudinally to bring the notch within said opening in the arm. Normally when` IIC once arrests the feed motion and the carriage stops. To hold the head b2 normally within the opening a2 in the tri p-arm, a spiral spring f2, Figs. 1, S, and l0, is employed on the triprod confined between the outer bearing ac of the rod and a collar g2, rigid on the rod. This spring acts to draw the head of the rod into the openin g in the arm when presented to the head, and thushold the feed mechanism in action. l

Besides its rotary motion the cutter is given .an 4alterna-ted lateral or sidewise motion in l line lwith its axis. (Indicated by the `full and dotted'linepositions of the cutter shown in Fig. '38.) This motion of the cutteris effected by means of a cam-wheel h2, Figs. 1,-8, 15, and 34, held to turn upon the cutter-spindle W,`adjacent to the gear V. -The cam-wheel has a continuous circumferential groove i2, occupied by a tongue 7a2 of a block Z2. (See Figs. 17 and 18.) The-block Z2 is adapted to slide freely upon the carriage O and against the side of the cutter-carrier N and is prc' vided with a threaded stem m2, in position to slide freely through a rectangular projecting part n2 of the carriage O. The stem, which is parallel with the spindle W, is provided with apair of threadedrings 02 p2 at one side of the body n2 and another pair of similar threaded rings r2 s2 at the opposite side of said part n2. These pairs of rings are adapted to be turned on the stem up against the part n2 or away therefrom, as may be required. The groove 2in the cam is made up of four parts-that is to say, two dwellsand two throws, alternated. The dwells are on opposite sides of the cam and of equal duration, each extending nearly half-way around the cam. The throws are equal and on opposite sides of the cam', one, t2, Fig. 18, being to the right, and the other, u2, Fig. 34, to the left, both being of brief duration. From this description it will be understood that the action of the cam as it turns will be to push and pull the stem m2 alternately through the part n2 of lthe carriage, holding it u-nmovable for a brief interval in each of its extreme positions. This is in case the threaded rings are turned sufficiently back, so as not to come in contact with the part n2. If, however, the rings be turned snugly against the part n2, as shown in Fig. 34,- the endwise or longitudinal motion of parts resulting from the action of the cam will be transferred from the stem m2 to the cutter-spindle V,`causing the cutter to move from side to side, as indicated in Fig. 38, and in these endwise motions of the spindle the whole cutter-carrier N, with the cam and gear V and other dependent parts, participate. c

I prefer to form the gear V and the coacting pinion y on the backshaft u, with spiral teeth, as shown, though bevel-gears might be employed instead. By using spiral teeth the gear V may move laterally across the shaft u and pinion, as in making the sidewise motions of the cutter already described, without interfering with the harmonious action of the pair.

' It is evident that if the rings be so located upon the stem that the distance between the pairs exceeds the horizontal length of the part n2 by the amountvof the throw of the cam (leaving the space o2, Figs. 17 and 1S) the cam will not act to move the cutter-spindle longitudinally. lt will be understood, also, that `if the width of the space n2 is less than the throw of the cam the spindle will be moved longitudinally by the camto 'the extent of the difference between lthe" width of said space and the throw of the cam.V By means of the threaded rings, then, the extent of the sidewise motion of the cutter may be regulated at pleasure. The two rings p2 and r2, adjacent to the partr, are graduated, as shown, an index 102 being provided for accurately reading the positions of these rings. The rings all turn independently of each other upon the stem, and in determining the lateral motions of the cutter in any given case the graduated rings are first set to their proper places on the stem and the outer rings then brought up snugly against them to keep them from turning, the pairs of rings in this respect acting as ordinary jam-nuts. The lead of the thread on the stem is made twenty to the inch, and the graduated rings are each divided into fifty equal parts, so that' by 'turning either index-ring through the distance of one space will serve to regulate the lateral position of the cutter to the amount of one one-thousandth of an inch.

The rings are set in every case so the cutter will be moved sidewise by the cam through a space just equal to the width of the points of the teeth of the cutter, this being clearly indicated in Fig. Cutters of different thickness or having teeth of different widths at the points are employed for formingv different sizes of gear-teeth, and the sidewise throw of the cutter is regulated accordingly by means of the rings.

The cam-wheel h2 is formed with internal teeth, as shown in Fig. 1G, and driven by a pinion :132, Figs. 15 and 16, rigid with the cutter-spindle WV'. 'A free intermediate gear y2 connects the pinion and the ca1n-'wl1eel, giving to the parts what is known as sun-andplanet motion, the motions of the parts be- `ing indicated by the several arrows in Fig.

16. The gear y2 has no xed axis, but rolls freely around the pinion as the spindle W is 4turned by means of the gear V.

The pinion m2 and gear V, Figs. 15 and 1G, are splined onto the cutter-spindle Wf in the :usual manner, the feather in the gear being shown at z2, both being held to place by a nut a3. (See Figs. S, 14, and 19.)

The taper-arbor for the cutter a', Fig. 15, is held lirmly in the spindle W by means of an axial rod b3, threaded into the arbor, as shown. p

The blank-gear spindle I, (shown in Fig. 21,) which turns freely within the spindlebarrel L, is formed to receive a taper-arbor X for holding the blank-gear K while teeth are being formed thereon. This arbor is formed with a reduced part c3 at its outer end, having three, more or less, longitudinal slits d3, Figs. 28 and 29, which constitutes a seat upon which to receivethe blank-gear. The arbor is hollow, the bore being slightly tapered or daring in the seat c3, and an axial expander e3 is provided within the arbor, having ak tapered part f3 to fill the tapered cavity IOCI IIO

Within the seat c3.

. vided Within the spindle and receives Within its inner end a threaded part g3 of` the eX- pander for the purpose of drawingthe latter` inward in a manner to cause the divided seat c3 to expand and` so firmly press the bore of the purpose, the holding-arbor for the blank 21, (see also Figs. 1, 14, 19, and

-theexpander e3. provided with holes z'vvith which to use a may be extended and provided With an over-Y hanging nut to hold the blank in place; but in cutting smaller bevels such a holding-nut would be in the Way of the cutter as the lat-, ter comes out at the small ends of the teeth.4

The arbor X is threaded upon its surface and provided with a threaded ring h3, 28,) in posif` tion to bear against the `end of the spindle I.

' By turningthe ring ,against the' end of they `spindle When itis wished to remove the arbor the latter Will be started out of the spindle,` the holdin g-rod Y being first unscrewedfrom` To turn the 'ring h3, it is Spanner-Wrench. o

The spindle-carrier H, Figs; 1, 14, and 20,1'os` secured tothe segment G by means of clampbolts k, their heads occupying the Wide parts of the T-shaped circular slots h and g. The inner side of the slot g is formed with teeth Z3, and a pinionfm3 is provided to engage said teeth, the shaft of said pinion being held in a seat in the carrier H. The outer end n3 of the pinion-shaft is squared for the purpose of receiving a Wrench or crank for turning the pinion. By this means the carrier H may be moved to any desired position upon the face of the segment Gr, its position in any givencase being determined by the `bevel of the blank to be cut. This spindle-carrier is f enlarged at o? and formed with a central transverse cavity or opening in Which to receive a split ring Z, Figs. 1, 2, 14, 20, and 21, encircling the spindle barrel L. The ring `is clamped upon thebarrel by means of a threaded stud 'p8 and handle r3 threaded onto the stud, the stud crossing the slit s3 in the ring. By tightening the ring atrany time firmly upon the spindle-barrel the latter and the spindle are prevented from` havingendwise motion in the spindle-carrier.

The spindle-barrel L is toothed along its under side, as shovvn at s, Fig. 22, and a pinion us (see also Fig. 2) is provided in the ring Z to engage said teeth, by means of which the spindle-barrel and the spindle may be moved longitudinally in the spindle-carrier to move the blank-gear toward or from the cone-center of the machine and into position to be act-ed The outer end 'v3 of the pinion-shaft (see also Fig. 1) is squared for the purpose of receiving a Wrench or crank An axialrod Y is pro-.I

r outside of the collar e4 ofthe shaft. t carrier f* has apart occupying the opening g4 'of the y'okeand held to thelatter by means for turning the pinion. The spindle-barrel is formed with aflongitudinal spline or groove of the usual kind appearing in F ig `2, theV inner bore of the carrier H and the ring Z being. provided `with feathers to occupy said spline, the feather in. the ring being shown at o7. .o i

'The spindle-barrel is formed atits upper or outer end Withahead A', Figs. 1, 2l, and 43,

to which is secured a hanger w3 (see also Figs.

2O and 23) for carrying the main parts of an indexing mechanism. .The hanger holds ashaft x3 in aplane at right angles to the axis of the spindle, AWhich shaft carries a Worm @f3 in a recess formed inthe hanger. The shaft is held in the hanger bymeans of a collare4 at one end and a screw p7, threaded in the opposite end, a Washeru rl' being provided under. the headof the 'screw to bear against the end of `the hanger. A Worm-gear B', rigid with the spindle, is engaged bythe Worm, the latter being central over the gear. The worm-gear is splined onto the spindle and held to place by athreaded ring z3, on the extremeend of the spindle, formed With holes CL4 for the puro pose of the use of a Wrench in turning it. The

spindle, asshown in Fig. 21, is formed with an enlarged part at its right-hand end to bear against the end of the spindle-barrel, andthe A Worm-gear B being held against the opposite end of thebarrel prevents endwise motion of the spindle Within the barrel. A yoke C', Figs.' 1, 20, 23, 24, and`43, is adjustably securedto the hangerws, as by a set-screw b4, Which4 serves to carry gearing and other parts of the indexing mechanism.

Upon the outer end of the shaft x3 and rigid therewith isplaced a pinion e4, held to place by means of a thumb-nut d4, the pinion being Aoi' a threaded nutor ring h4, formed with circumferential openings t4 `for the `use of a Wrench; A shaft 7a4, central within the holder f4, serves to hold4 a gear Z4 in position to engage the pinion e4. The shaft has a journalbearing in the holder f4 and is held to place bymeans of an end screw m4 and Washer.

The gear turns with the shaft, and a crank n4,

adapted toturn the shaft, is placed upon the' latter outside of the gear and held to place by a thumb-nut o4.

Now it Will'be understood that by turning the crank the Worm 'g3 Willbe turnedl and so Athe spindle I with the blankgear K. The

holder f4 is provided with a chambered barrel p4, occu pied by a detent r4, actuated by a spring s4. The' detent is parallel with the shaft 7a4, having its head slightly projecting from the end of the barrelmto engage and hold a tooth t4 rigid with the crank. (Clearly shown in'Figs.^2O and 23.) "The tooth t4 is oppositeoron a line with the handle n4 of thecrank, the latter being extended across r its axis and provided with another rigid tooth g4, similar to the tooth i4, in position to meet IOO .los

A detento IIO `its axis.

the detent Ywhen the 1 crank is turned half around. On account of thetwo teeth t4 and y4`thecrank may be caught and held by the detent at every half-revolution.

A releasing-lever v4 (see also Figs. 19 and 24) is provided by means of which the detent may be drawn within the barrel p4, thus releasing the crank. This lever is held to the detent by means of a pin w4,and it occupies a shallow rectangular cavity c4 in the end of the barrel, within which cavity the lever acts. The head of the detent is form ed witha notch in which to'receive ai tooth of the crank,'at

either side of which notch the head is beveledl or inclined, so that when turning the crank and a tooth encounters the detent the latter 'will be pushed .backagainstthe spring and allow the tooth to glide into the notch. By

loosening the nut h4 the.detent-holder]L14 may be moved anywhere along the slot g4 of the yoke forj the purpose'of changingv the pinion c4 -as ma be re uired. The'vfearl4 has sixt `teeth and is constant, but pinionsfof different diameters arefsubstituted forthepinion c4, according to the number of the lteeth 'to be cut upon the blank-.gear K. As the machine is constructed with *sixty teeth onthe worm-gear'B, there will be formed as many y teeth on the blank Kas there are' teeth on. the 'pinion c4,turning the cran-k through onel complete revolution at each operation of indexingV the blank.

Besides the rotary motion and the lateral recurrent motion .given the cuttergas: abovef described, it, with all the.partsrestingupon the bracket or kneeC, isgiven'ahorizontal circular reciprocating motion'in therplane ofy The `base-block l?, with :allof lthey 'lsuperincumbent parts, is adapted Vto swing. 40 f A'face`:zl, Fig. 9, of the knee. `A circular SV- `shaped groove a5, Figs.`1, 8, V9, `and 35, is formed .intheupper'face of the knee concentricwith the shaft U,.the under face of thebasefblock being lformed with a corresponding circular ,V-shaped .ring or beadl, Fig. 41, to occupy. saidgroove. l zHeadedstuds c5 c5,.Figs. 9 and|` 41, projecting upward througlrslots d5 inthe knee'an'd threaded intothe base-block, hold the latter in contact .with the surface of the :knee,.but allowingit to swingfrcely.there on. .An oscillating arm D', Figs. 1,8, 1.2,'andy horizontallyupon the upper horizontal'v plain 35, resting horizontally uponth'eupperend yof the lcolumn A, is connected withthe baseblock P, preferably'with a vertically-'sliding joint-fas, for-example, adovetail bearing e5.

This'manner of :connecting theparts permits of avertical motion for the knee and baseblock, while the arm retains its position on'the column. The ordinary gib and set-screws z5 are usually employed in the arm to coact with the column. armD normally at right angles and is pro i dinally-therein.

The reciprocator crosses the vided with a rigid vertical stud h5, Figs. S and 11, extending into a cavity l5in the arm. A block h5, fitting the stud with a journahbearing, occupies said cavity in the arm, tting the walls of the latter at two opposite sides, but leaving spaces at its opposite ends, so that it may have a slight longitudinal motion in said oscillating arm. The cavity in the arm and contained parts are covered by a cap Z5, (see also Fig. 35,) held to place by simple fasteners m5,`threaded in the stud. r

The bar g5 is reciprocated by means of gearing within the column. (Shown in Figs. 3, 10, 12, and 13.) The columnisformed with an opening or doorway A2 through its `side wallitorender the parts within accessible, the

openingvbeing closedby a door'L, Figs. 1, 10, and v19. F. is a rock-wheel having teethpart lway around its circumference adapted to engageteeth a5 onthe under surface of the reciprocator. This'wheelis rigid with a short shaft 0.5, adapted to turn in a bearing pirigid `with Aawall ofl the column A, the shaft being `held in place by an end screw 115. Figs. 14 and 19.1)

The driving-shaft S, Fig. 10, is provided 'with a'rigid pinion S5, which turns a gear t5,

(See Valso (see also Fig. 3,) rigid with a=short shaft a5,

journaled ati6 and a6 in the sides of the column, Figs. 3 and25. Upon theshaft ware placedloose companion pinions c5 and v105, kwhich engage,'respectively, twin gears x5 and g5' of one piece, Fig. 44,`turning upon a Vhorizontal stud or shaft F', made `rigid with the column. Theshaft'is held direct-ly by'a flanged bushingzK, (see Figs. 10,`14,'and 44,)

:securedzto the column by simple means, as shown. .Thetwin gearis formed with a transverse race a6,=Figs. 3 and 10, in which ablock IOO yofthe block-Ja crankmotion when thefgear is turned. .A rod G connects the gear withy the fwheelE' by being joined to the pin c? and the .stud di?, rigid in the wheel. `set nearer the center of the gear than the stud #d6 is'to the center of the wheel, a revolution ofthe former gear will cause the wheel to rock The pin being reciprocall-y and not revolve.

`One or the other of the loose'pinions v5 105 `on the shaft a5, Fig. 10, may be made to turn with the shaft and drive the parts connected with it by means offa sliding key H', (see Figs..25 and 27,) reaching without'the column, as shown in Fig. 14. This key, which always turns kwith the shaft, consists of a -stem occupying .an axial cavity m6 in the end IIU around therein without contact with either ley R rotates the cutter a,

vided, formed with teeth at its when the key is'in the right position. Each pinion is further formed with an additional keyway or cavity r6, extending longitudinally inward from the space p6, adapted to receive within it the projecting part of the key when the pinion is turned to position. Now when the key occupies its central position, as shown in full lines in Fig. 25, no motion will be imparted'by the shaft a5 to either pinion; but should the key be pulled outward to the position shown by dot-l ted lines at the right the pinion 105 would be locked to the shaft and so turn with the latter and drive the twin gear and connected parts, the pinion uturning loosely or idling, or should the key bepressed inward to occupy the dotted position at the left the pinion o5 would be locked to the shaft and become a driver, lche pinion widling. By these means the revolving of the driving-belt pulreciprocates or swings it with various connected parts upon the knee C, as indicated by full and dotted line positions in Fig. 35, and `also moves the cutter in the line of its axis or tangentially' to the periphery of the gear-blank being op` erated upon and radially relatively to the center of its swinging movement. The pinions o5 and 105 being of different diameters, as shown, the key not only serves to change` the rate of the swinging motion of the cutteigf The drivingpulley also serves to Acause the blank-gear spindle 'to' rock recip-` Vrocallyin its bearings in the spindle-barrel, I as described farther on.

The arm D is formed with an upturnedl part c6, Figs. '1, 4, and 8, at its outer end, vto` which is secured, by means of a clamp-screw? a rest or carrier gf", holding a horizontal toothed crown-segment h6, (see also Figs. 3j 6, 19, 30, and 55,) adapted to slide therein.4 The segment is also formed with teeth t, Fig. 6, in itslower side within the carrier g, and a travelingwheel k6 (see alsoFig. 5) is proupper side to engage the teeth t of the segment. The wheel 7c is adapted to ,turn upon a stud l, made rigid in the carrier 96, as clearly shown in Fig. 4. 86 is a track upon which the blank part of the wheel is adapted to roll, secured to the column'loy` means of a clamping-bolt m6. This track is vertically adjustable, usualf means (notshown' and not involving inven-- tion) being provided for keeping its upper; surface always level.l The wheel and track are conical, all divergent lines running to the cone center of the machine, likewise the teeth on both sides of the segment h6, and said seg-v ment with the track s and Vthe carrier Q6 for the segment are likewise curved concentric with the cone-center, as shown in the various figures. The segment h6 rests in a circularA cavity in theupper surface of the carrier g, inclined or dovetailed at the outside, as shown.` in Fig. 4, the inner face of the rack bearing.

the proper relative i againstthe part c6, near its upper'end. The outer face of the upturned part e of the oscillating arm Dis curved vertically concentric with said cone-center, as appears in Fig. 4, likewise the outersurface of the column A, against which the track s6 bears.

The part e6 of the arm Dis formed with a vertical slot r6, Figs. 4and 12, for the clamping-bolt f6, and the track s6 is formed with a vertical slot 1116, Figs. 3 and 4, for thebolt at, by means of which the various parts controlledby those bolts may be vertically` adjusted. A vertical holdin g-screw Lz/6, (see also Fig. 1,) threaded in a lug a, projecting from the side of the column A, bears at its point against the lower face of the track s, by means of ,which to assist in vertically adjusting it. y

The outer face of the part e6 of the oscillatf ing arm is formed with a vertical groove a7, Fig'. 12, and the carrier g6 is formed with a corresponding vertical tongue 117, Figs. S and 35, to occupy the groove, on account of which the carrier can have no other motion upon the arm than upward or downward. j

From the foregoing description of the relal tion and the action of the parts it will be un# derstood that as the oscillating arm Dswings from side to side the wheel it will roll along the track s6 and'cause the crown-segment h to slide reci procally in its bearings in the car- .,rier Q6. but also to stopits swinging motion alto` -gethein I', Figs. `1, 3, 4, 19, and 30, is a curved rock- IOO ing arm connecting t-he crown-segment h6 with the spindle-barrel L, above the spindle-carrier H; The lower end or foot of this arm is expanded and curved and formed with teeth to be engaged by the teeth on the upper face of the crown-segment and adapted to roll therewith as the latter is reciprccated. (ClearlyV shownl in Fig. 30.) The upper end ofgthe rocking arm is j oinedto a ring N', Figs. 1, 14, 19, and 20, secured to the spindle-barrel L by a set-screw 37. Bythese means the reciprocations'of the crown-segment cause the blank-gear K to reciprocally rock or turn upon its axis through short arcs of a circle. VIf the wheel k6 were to' rolluninterruptedly upon the track s6, the segment, it will be understood,` would move in each direction through a dist-ance twicethat which the wheel Arolls upon the` track or approximately twice the distance through which the outer end of the arm D swings. This extreme travel of the segment is provided to' meet the requirements of any casefthat may occur in forming teeth on gears of all diameters within the limits of the machine and degrees of bevel; but it Would'turn the blank-gear through a larger arc of circle than usually necessary to give the teethformed upon the blank the desired form of crossvsection. u

To regulate the extent of the travel of the crown-segment, and consequently the rocking of the blank-gear, arresters c7, Figs. 3, 5, 6, and 30,]arc providedA for the wheel 706.

`These arresters-are iiat taperedpieces,` each IOS IIO

wheel, as shown in Fig. 5. The fiat bases (Z7 of the arresters are tangent with the wheel and adapted to meet and slide upon the track,

as shown in dotted positions in Fig. 30, as the wheel rolls to the right or to the left. These arresters ,lap upon each other at their small ends and are held to turn upon an axial pin e7 in the stud Z6 of the wheel. (See Fig. fl.) Clamping thumb-screws f7 are proyided to hold the arresters in their positions of adj ustment. These screws are threaded into blocks Q7, Fig. 5, in a circular dovetailed groove hi in the side of the wheel, the blocks being inserted through an opening t7, Fig. G. When the wheel rolls in either direction upon the track-as, for instance, toward the right, as shown in Fig. 30-the foot of the arrester on that side will be brought down Hat upon the track and stop the rollin gvmotion of the wheel and cause the latter to slide thence to the end of its motion in that direction.

f While the wheel is rolling the crown-segment h6 will move, as has been stated, twice as rapidly as the axis of the wheel; but the `moment the arrester begins to act and causes the wheel to slide the segment will then move simply `as the wheel moves and no faster than its axis and the carrier gG. The wheel is graduated on its face under the arresters, as shown, the zero-mark being vertically downward, for instance, when the segment is centrally within the carrier and the arm l vertical, as appears in full lines in Fig. 30. The graduation-marks are read alike each way from zero and at the knife-edges i7 of the arresters. It the arresters are, to illustrate, turned back out of the way, s0 as not to touch the track during the rollings of the wheel, the crown-segment will be given its maximum or extreme motion or throw and cause the blank-gear to roll through a large arc of cir- On the other hand, if the arresters are both brought down to the zero-line the wheel will not roll at all, but slide in either direction as the oscillating arm D swings to the rightl or to the left, thus giving the segment its minimum throw or travel and turning the blank but little. Any extent of motion between these two extremes may be given the segment by setting the arresters nearer to or farther from the nero-line, and in practice the arresters are set so as to cause the blank-gear l to reciprocate through an angular distance equal to the angular distance between adjacent teeth being formed on the blank-gear at v the pitch-circle.

An inspection of Fig. 30 will make the relative motions of the parts clear. If the parts are,to illustrate, in normal positions, as shown in full lines in the igure, and a motion of the oscillating arm D sets in toward the right, the rolling of the Wheelwill bring the righthand arrester down onto the track, as appears in dotted position ci.A --During this movement the wheel will advance to the position shown -spindle and the crown-gear segment.

by dotted lines 708, carrying .with it the crownsegment to the dotted position-h8 and the rocking arm to the position in--dotted lines at l2. The continued motion of the oscillating arm, which has yet some distance to travel beforcits swing in that direction is completed, will cause the wheel and the arrester to slide to the respective dotted positions k and a9, the segment and rocking arm assuming the respective positions 7L and I3. (Shown in dotted lines.) These relative motions of the parts, it will be understood, also take place in an opposite direction when the arm -D is swung toward the left. rlhese continued motions of the crown-segment and rocking arm in opposite directions after the wheel begins to slide serve to bring the faces of. adjacent teeth alternately to the vertical plane k7, Fig. 38, hereinbefore described.

The graduated spaces upon the wheel are not made with reference to the degrees of a circle of the diameter ofthe wheel, but each major space covers a degree of a circle whose center is, say, at the cone-center of the inacl1ine,with radius reaching to the outer end of a tooth of the crown-segment, so that by setting the arresters to the marks upon the wheel, as shown' in Fig. 45, the extent ot' `travel ot' the crown-segment may be regulated in amounts corresponding to fourths of a degree of said large circle.

The cutter is set by means of the screw E for controlling-.the knee C, so that the points of its teeth touch at its upper side a horizontal plane O', Fig. 33, passing through the conecenter, and in setting the blank-gear the latter is brought in position, so that the line of the root of a tooth or the bottom of a space between adjacent teeth coincidesv with said plane. The face of the circular segment G, Fig. 1, is graduated or marked in degrees of a circle and the spindle-carrier lI or .holder for the blank-gear is set in any given case with reference to this scale on the segment, the iigures being read at t7 at the upper side of the carrier. Rocking arms I of diierent lengths are provided to be inserted in the machine, according to the position of the carrier H upon the segment. Each arm when put in place is secured rigidly to the ring N by means of the bolt u?, the curve of the toothed foot of the arm being regulated according to the length of the arm, or, more accurately,

IOS

IIO

the angular distance between the axis of the The vertical adjustments of the segment-carrier g and track s6, heretofore described, render but few arms I necessary, as such adjustments meet the requirements of many kinds and sizes of blank-gears.

The connection between the oscillating arm D and the blank-gear spindle is positive, rendering the rocking of the gear positive with the swinging of the cutter. l

The gear Y, Figs. 19 and 3l, is adapted to slide longitudinally upon the shaft u, the latter being splined, as shown, and the gear beige ing supplied with an ordinary featherpcc'up'ying the spline. rThe shaft has no endwise motion, and the hanger or bearing ne, `which contains and controls said gear, being sebeing necessarynamely, the sidewise motion or thrust of the cutter, hereinbefore fully described, and shown in Fig. 38. The cam h2, which produces these sidewise motions or thrusts of the cutter, is timed toturn through one revolution while the cutter makes four revolutions, and the thrusts of the cutter are also timed with reference to the rocking of the blanlegear and the swinging of the cutter-that is to say, aside thrust of the cutter is made every time the blank-gear rocks in either direction, and consequently every time the cutter Aswings to one side or the other, the

side thrusts being made quickly at the terminations of the swingings of the cutter. 0n account of these motions one side and then the other of the cutter acts on the opposing faces of two ad jacentteeth of the blankfgear. These sidewise motions of the cutter are made accurately with reference to a vertical plane passing through the cone-center c?, Fig. 37. (Represented by the dotted line 767 in Fig. 38.) In one position of the cutter the corners Z7 of the points of the teeth coincide with the plane, while in the other position of the cutter the other corners m7 of the points of the teeth coincide with the plane, this plane, be

it understood, not being fixed, but partaking of the swinging motion of the cutter. Each side of the cutter shapes a side of the tooth,

and the Glitter may be just wide enough to come through the small end of a space between teeth.

On account of the motions given the cutter it will iinish the teeth of a bevel-gear with one setting of the machine,y using only one cutter, a single revolution only of the gear being necessary to finish the teeth.

On account of the upper face e4 of the knee C being horizontal and all the parts resting thereon moving horizontally when being swung by the reciprocating bar g5 the swinging motions of the machine are easy, and

p these reciprocations of the parts may be made rapidly without any shock or jar to the ma# chine. v e

It will be observed that in this machine what the cutter really does in successively passing through the blank is to accurately form the spaces in the face of the blank. Each space is formed by the cutter (which is single and solid) passing once through, and the spaces being correctly formed results in corrcctly-formed teeth. The machine does not in any instance form both sides of a tooth simultaneously or while the cutter passes once through the blank, but, rather, both side walls and the bottom of a space between two teeth are completed each time the cutter passes through. 4

"The relative positions of` the cutter .s and a gear-tooth 107 being formed," resulting from the rocking of the gear and the simultaneous swinging of the cutter, are shown in Fig. 36. When both are at the extreme left, for example, the cutter is actingat the root of the tooth, and as both move toward the right (the cutter swinging and the gear rocking) the tooth will rock across the face of the cutter, the latter finishing at the point of the tooth, as shown by dotted lines 107 and c at the right. The side thrust of the cutter now taking place toward the right brings the opposite side of the cutter Z74 against the other wall of the space or face of the adjacent tooth m7, near its root, and as both tooth and cutter now return to the left the former will rock across the face of the cutter from root to point. An opposite sidewise motion or thrust of the cutter taking place at this juncture brings the cutter and the tooth 207 again into the positions shown at the left in the figure. Thus the cutter shifts quickly and frequently from one side wall of the space to the other,

(or from the face of one tooth to the opposing face of the adjacent tooth,) doinga little work upon each alternately as the feed gradually carries the cutter along from the large end to the small end of the space.

The two eXtreme positions of the cutter assumed on account of its swinging :motions are shown by full and dotted lines in Fig. 37. In this figure the cutter is shown as in a neutral IOO position, so far as the side thrusts are concerned, the middle plane of the cutter pass ing through the cone-center c7.

This machine is adapted to cut the parallel teeth of spur-gears as well as radial' or tapered teeth of bevel-gears. To cut the teeth of spur-gears, the spindle-carrier II is brought down to the zero-line, reading at the upper edge of the carrier, as in lother cases. In this position of the partsthe axis of the blankgear spindle will be horizontal and intersect the axis of the shaft U at right angles. The cutter is lowered to bring the plane of the points of its teeth at the upper side to coincide with the line at the bottom of a space between teeth. In cutting spur-gearsI the latter are not rocked on their axes and the cutter is not swung or moved laterally by the cam, the cutter having no motion other than the rotary and the feed motion. For this parallel-tooth work the cutter is set so that its central vertical plane coincideswith. the planet@ Fig. 38, the feed motion of the cutter being toward the cone-center along 'said plane. In this work the cutter needs to beformedwith curved sides and of the'l right thickness to give the spaces in the blank-gear a correct form of cross-section- None of the IIO parts of the machine used for cutting radial teeth are inthe way or have to be removed for cutting parallel teeth. The key II', controlling the companion pinions in the column, is set so as to clear both pinions, and the pairs of threaded rings on the stem 'm2 are turned back, so as to not encounter the carriage O. This prevents the swinging motion andthe side thrusts of the cutter and the rocking of the gear.

In using this machine the blank-gears, whether conical or cylindrical, are iirst turned to the proper size and shape, the surface to be cut corresponding with the points of the teeth.

For cutting a bevel-gear, for instance, the blank is mounted upon the blank-gear arbor and the blank-gear carrier H is moved upon the segment G until the root angle of the blank is read at t7 on the carrier. The root angle of a gear isv the angle between the axis of the gear and the line of the bottom of a space between adjacent teeth. The blank gear spindle is then moved endwise until the rootline of a tooth passes through the cone-center of the machine. The cutter is adjusted vertically, so that the point of a tooth at the top g x gears, the combination, with a gear-blank coincides with the root-line, and adj usted laterally,so that one side-say the right-side,Fig. ISS-of the points of its teeth will be in a vertical lane k7 assin r through the cone-cen`- ter. Now set the jam-nuts o2 p2, Figs. 8 and 18,. .up against the part n2 of the carriage O and bring the other pair of jam nuts or threaded rings r2 s2 so that the space o2 shall equal the difference between the throw of the cam andthe thickness of a point of ay tooth. Set the 'arresters for the traveling wheel k6, Fig. 30, so that the distance between them is equal in degrees (asl marked on the wheel) to the width in degrees at the pitch-line of a space to be cut in the blank-gear. Set the crank-pin c6, Fig. 3, of thev twin gears in the column to give the cutter a swing sufficient to clear' the cut. Iut into the machine a rocking arm I of proper length and vertically adjust the crown-segment h2 so its upper teeth will properly engage the teeth of the rocking arm. The rate of the feed is regulated by moving the feed-ring s, Fig. 8, toward or from the aXis of the feed-shaft, according to the material of which the blankgear is made and the size of the cross-section of the space between teeth. In cutting the spaces of steel blanks the feed needs to be much slower than when cutting the spaces in blanks of cast-iron or other softer material.

The sidewise motion or thrust of the cutter is in every case, as has been already stated, equal to the width of the point of a tooth of the cutter. As a matter of convenience I formthe cam-wheel with an ultimate throw of one-fourth of an inch, which is the Width of the points of the teeth of the widest cutter used in the machine. pairs of `adjusting-rings in any given case the Then in setting the space o2 between either pair and the inter- `mediate stop-piece 'n2 of the carriage O is 1.` In a machine for forming the teeth of* I gears, thecombination with a gear-blank holder, of a cutter, and means for simultaneously moving the cutter circularly and tangentially relatively to the periphery of the gear-blank, substantially as set forth.

2. In a machine for forming the teeth of gears, the combination, with a gear-blank holder, of a cutter, and means for simultaneously moving the cutter circularly, tanv`gentially, andv radially, substantially as set iforth. v

3. In a machine for forming the teeth of j gears, the combination with a gear blank f holder, of a cutter movable circularly, tangentiall'y, and radially, and means for varying the circularA movement relatively to the l radial movement while the tangential movei ment remains the same, substantially as set l forth.

4. In a machine for forming the teeth of holder, of a cutter, and means for moving j the holder axially, and means for moving the l cutter circularly and tangentially relatively Q to the periphery of the gear-blank, substan- 5 tially as set forth.

5. In a machine for forming the teeth of gears, the combination, with a gear-blank holder, of a cutter, and means for moving the holder axially, and means for moving the .y cutter circularly,; tangentially, and radially,

the tangential movement being relatively to the periphery of the gear-blank and the radial movement being relatively to the circular movement, substantially as set forth.

6. In a machine for forming the teeth of gears, the combination, with a gear-blank holder, of acutter, and means for moving the cutter circularly, and tangentially, the tangential movement being recurrent relatively to the periphery of the gear-blank, substantially as set forth.

7. In a machine for forming the teeth of gears, the combination, with a gear-blank holder, of a cutteigvand means for moving the cutter circularly, taugen tially,and radially, the tangential movement being recurrent, and the circular'movement varying in extent relatively to the radial movement, substantially as set forth.

8. In a machine for forming the teeth of gears, the combination, with a gear-blank holder, of a` cutter, and means for simultaneously moving the cutter circularly and tani gentially, and stops for limiting the amount of tangential movement, substantially as set forth.

9.L In a machine for forming the teeth of gears, the combination, with a gear-blank IOO IIO

holder, of a cutter, and means for moving thel relatively to the periphery of the gear-blank and the radial movement being relatively to the circular movement, substantially as set forth. l

11. In a machine for forming the teeth of gears, the combination, with a gear-blank holder, of a swinging base-block pivotally secured adjacent thereto, a cutter-support mounted upon the block and movable at a tangent to the periphery of the gear-blank, and means for simultaneously moving said block and cutter-sup port, substantially as set forth.

12. In a machine for forming the teeth of gears, the combination, with a gearblank holder, of a swinging base-block pivotally secured adjacent thereto, a cutter-carrier mounted upon the block and movable tangentially to the periphery of the gear-blank, and a cutter-spindle in the carrier, substantially as set forth.

18. In a machine for forming the teeth of gears, the combination, with a gear-blank holder, of a swinging base-block pivotally secured adjacent thereto, a carrier mounted upon the block to move tangentially to the swinging movement ofthe block, a projection upon the carrier, a stem movable longitudinally through said projection, stops upon the stem, a spindle in the carrier, and means for moving said stem, substantially as set forth. l

14. In a machine for forming the teeth of gears, the combination, with a gear-blank holder, of a swinging base-block pivotally secured adjacent thereto, a carrier mounted upon the block, a cutter mounted on the carrier, a longitudinally-movable stem adjacent to the carrier and adapted to engage therewith, a cam-wheel adjacent to one end of the stem provided with a groove for moving the stem, said groove being provided with two throws and two dwells, substantially as set forth.

15. In a machine for forming the teeth of gears, the combination, with a gear-blank holder, of a rotary cutter movable circularly, tangentially, and radially, and means for simultaneously stopping the rotary, tangential and radial movement of the cutter, substantially as set forth.

16. In a machine for forming the teeth of gears,` the combination, with a gear-blank holder, of a radially-movable rotary cutter,

and means for rocking the holder axially at variable 'rates of speed, substantially as set forth. l

17. In a machine for forming-the teeth of gears, the combination, with a gear-blank holder, of a laterally-movable cutter, an arm for locking4 the holder axially, and means for movingthe free end of said arm at different rates of speed, substantially as set forth.

18. In a machine" for forming the teeth of gears, `the combination, with a gear-blank holder, of a swinging base-block pivotally secured adjacent thereto, a cutter upon the base-block, an'arm connected with the blankholder, a wheel connected with the base-block formoving the arm, and means for locking the wheel against rotation during a portion of the swinging movement of the base-block, substantially as set forth.

V19. In a machine for forming the teeth of gears, the combination, with a gear-blank holder, of a-swinging base-block pivotally secured adjacent thereto, an arm for moving the block, a wheel upon said arm, an arm connected with the blank-holder, a rack between the end of `the blank -holder arm and the wheel, and means for locking the wheel against rotary movement during a portion of the swinging movement of the arm on the base-block, substantially as set forth.

20. In a machine for forming the teeth of gears, the combination with a gear-blank holder, of a base-block pivotally secured adjacent thereto, an arm for swinging the block, the free end of which is provided with a wheel,

IOO

a track for the wheel, an arm connected with track, substantially as set forth.

21. A machine for forming the teeth of r gears, having a rotary cutter adapted to move sidewise in the line of the axis of its rotation, and means to give it said sidewise motion, and a feed motion for the cutter, in combination with a holder for the blank-gear, and

means for rocking the latter, said sidewise motions of the cutter being timed with reference to the rocking of the gear, said motions being automatically variable relatively to each other, substantially as described.

22. A machine for forming the teeth of gears, having a rotary cutter adapted to move sidewise in the line of the axis of its rotation, and means to give it said sidewise motion, and a feed motion for the cutter, in combination v with a holder for the blank-gear, and means for reciprocally swinging the cutter and for rocking the blank-gear upon its axis,

the said sidewise motion of the cutter being made at the termination of each swing of the cutter, substantially as shown and described.

23.. A machine for .forming the teeth of gears, having a rotary cutting-tool adapted to have sidewise motion in line with the axis of its rotation, and means to give it said side- IIO 

